Mixing apparatus



Oct. 10, 1967 H. A. SCHUBERT MIXING APPARATUS Filed Aug. 15, 1966 HARRY/1. scuusmt fnwhu 5M Arronun:

United States Patent 3,346,241 MIXING APPARATUS Harry A. Schubert, Waterford, Wis., assignor to Schubert Auto-Body Tools, Inc., Union Grove, Wis., a corporation of Wisconsin Filed Aug. 15, 1966, Ser. No. 572,400 9 Claims. (Cl. 259-72) ABSTRACT OF THE DISCLOSURE The invention relates to a fluid operated mixing device, including a base having a cup-shaped support member which removably supports the motor of a portable fluid drive unit. The drive shaft of the motor carries a disc or turntable, and a shoe is mounted eccentrically on the disc and supports a container of the material to be mixed. The upper end of the container is similarly supported by a second shoe mounted through a resilient member from an arm which extends outwardly from a column supported by the base.

The fluid drive unit includes a handle having a fluid flow passage and a trigger-operated valve which controls the flow of fluid in the passage. When the fluid drive unit is inserted in the supporting cup, the trigger is automatically depressed to open the valve :and permit the flow of fluid to the motor.

This invention relates to a mixing device and more particularly to a device for mixing paints or the like.

When repainting the reworked portions of vehicle bodies, the pigment must be thoroughly distributed throughout the paint, for if the pigment is not thoroughly mixed, the paint as applied to the body may be slightly oft-shade and any off-shade coloring is extremely noticeable on vehicle bodies. This problem is particularly apparent when using metallic type paints or lacquers having heavy metallic pigments which are diflicult to thoroughly mix by hand.

Larger auto body shops have mechanical paint mixers to mix the paint or lacquer. These paint mixers are generally quite expensive and small body shops normally cannot aiford the outlay for the conventional automatic type of mixer, so they rely on hand mixing and attempt to obtain a complete distribution of the pigments.

The present invention is directed to an inexpensive apparatus for mixing liquids such as paint and lacquer, and more specifically to a mixing unit which utilizes the pneumatic-drive mechanism of a standard oscillating sander. Almost all body shops, regardless of their size, have an oscillating pneumatic sander and the pneumatic drive mechanism of the conventional sander is incorporated to operate the paint mixer of the invention, resulting in a low cost, yet extremely etfective mixing device. According to the invention, the paint mixing device includes a base having a cup-shaped support member which supports the pneumatic motor of a conventional oscillating sander. The drive shaft of the motor carries a disc or turntable and a resilient shoe is mounted eccentrically on the disc. The shoe supports a can of paint to be mixed, and the upper end of the can is similarly supported by a second shoe mounted through a resilient member from an arm which extends outwardly from a column supported by the base.

Air or other gas is supplied to the motor through the handle of the pneumatic drive mechanism, and in the conventional drive mechanism the air flow to the motor is controlled by both a variable flow valve and a triggeroperated, on-off valve. Extending upwardly from the base is a stud which is positioned to engage the trigger when the pneumatic drive mechanism is inserted in the supporting cup, and depressing of the trigger by the stud automatically opens the on-otf valve for air flow. The flow of air to the motor is thus controlled by manual operation of the variable flow valve. In operation, the eccentric connection of the can-supporting shoe to the motor drive shaft serves to oscillate the can and mix the paint. The spring connection between the upper shoe and the supporting arm aids in developing a fast, effective shaking motion for the can which thoroughly mixes the pigment in the paint or lacquer.

The mixing device of the invention is an inexpensive device which incorporates the pneumatic drive mechanism of a standard oscillating-type sander normally available in auto body shops. The device can be readily converted to use as a paint mixer by merely removing the supporting disc of the sander and installing the flexible can-supporting shoe.

The supporting shoes are designed with a series of concentric recesses enabling the shoes to engage either pint, qu-art or gallon cans without changing or altering the shoes.

The mixing device is considerably cheaper than the conventional paint mixing units which require an integral motor and drive mechanism. Therefore the unit is adaptable for use in small auto body shops which cannot afford the initial outlay required for the conventional paint mixin g equipment.

Other objects and advantages will appear in the course of the following description:

The drawings illustrate the best mode presently contemplated of carrying out the invention.

In the drawings:

FIGURE 1 is a side elevation of the paint mixing appanatus of the invention with parts broken away in section;

FIG. 2 is a perspective view of the base and supporting structure for the upper shoe;

FIG. 3 is a sectional view taken along line 3-3 of FIG. 1;

FIG. 4 is a section taken along line 44 of FIG. 1; and

FIG. 5 is an enlarged fragmentary side elevation with parts broken away in section showing the supporting structure for the shoes.

The drawings illustrate an apparatus for mixing materials, such as paint, lacquer or the like, which includes a base plate 1 having a series of notches 2 to receive bolts for attachment of the base 1 to a work bench or other supporting structure. Extending upwardly from the central portion of base 1 is a cup-shaped member 3 which receives and supports the motor 4 of a conventional pneumatic drive unit, indicated generally by 5, for an oscillating sander. The pneumatic drive unit 5 is of standard construction and in itself forms no part of the present invention.

A drive shaft 6 extends upwardly from motor 4 and carries a disc 7, and an internally threaded connector 8 mounted eccentrically with respect to disc 7. To attach the connector -8 to the disc, the lower end 9 of the connector is threaded within an opening in the upper surface of disc 7.

As best shown in FIG. 5, a stud 11 having its head imbedded within a flexible shoe or boot 12 is threaded within the central opening in the connector 8. A can 13 adapted to contain a material to be mixed is supported on the lower shoe 12, and an upper shoe 14, similar in construction to shoe 12, engages the upper end of can 13. Shoes 12 and 14 are preferably constructed of a resilient material such as rubber, plastic or the like, and are each provided with a pair of circular recesses 15 and 16. The inner or smaller recess 15 of each shoe is provided with a diameter sufiicient to snugly receive the end of a pint can external diameter such that the head on a gallon can of paint will engage the periphery of the shoes, as shown in FIG. 5. With this construction the shoes 12 and 14 will engage :and hold either .a pint, quart or gallon of paint without any alteration or changing of the shoes.

The head of a stud 17 is embedded in the upper shoe 14 and the stud extends through an opening in a washer 18 and is engaged by a nut 19. Coil spring 20 is secured by welding to the washer 18 and the opposite end of the spring is welded to a cap .21 which is attached by bolt 22 to an arm 23 which extends outwardly from column 24. The lower end ofthe column 24 is secured to the base 1.

To provide an adjustable connection between the arm 23 and the column 24, the inner end of the arm carries a sleeve 25 which is slidable on the column and is secured in any desired position on the column by set screw 26.

As best shown in FIG. 2, the cup 3 is provided with a notch 27 which receives the handle 28 of the pneumatic drive unit 5. A hose 29 connected to a suitable source of pneumatic fluid is connected by a fitting 30 to the outer end of handle 28. Handle 28 includes an air passage, not shown, which provides communication between the hose 29 and the air motor 4 and a variable flow valve is located in the passage and is operated by a lever 31 which is mounted for rotary movement on the outer surface of handle 28. By rotating the lever 31, the flow of air through the passage within the handle 28 can be regulated between a full-open to full-closed position.

In addition to the variable flow valve mechanism controlled by lever 31, an on-oif valve is also positioned in the passage within the handle 28. The on-otl valve is connected to a stem 32 having a head 33 which is located beneath the handle 28. The valve stem 32 is retained in position by a retaining member 34.

By moving the valve stem 21 upwardly the on-ofi valve is opened to permit free flow of air through the passage within the handle 28. The valve stem 32 is actuated by a trigger 35 which is pivotally secured to brackets 36 extending downwardly from handle 28. Brackets 36. are adapted to extend through a notch 37 formed in the cup 3 beneath the notch 27.

As shown in FIG. 1, the trigger 35 is provided with a bend 38 which bears against the head 33 of valve stem 32. When the motor 4 is positioned within the cup 3 the outer end of trigger 35 is engaged by a stud 39 which extends upwardly from the base 1. Moving or depressing the trigger to the full line position as shown in FIG. 1, raises the valve stem 32 and opens the air passage to the motor 4. As the on-oiT valve controlled by the valve stem 32 is thus permanently opened, air flow to the motor can be manually controlled by rotating the valve lever 31.

As previously mentioned, pneumatic drive unit is a standard part of a conventional oscillating sander. When it is desired to use the drive unit for paint mixing, the sanding disc is removed from disc or turntable 7 and the lower shoe 12 is engaged with the disc 7 by threading the stud 11 into the connector 8. After the shoe 12 has been mounted on the pneumatic drive unit 5, the motor 4 is positioned in the cup 3 and the trigger 35 will be depressed by engagement with the stud 39 to thereby open the on-ofi valve in the handle 28. The arm 23 is then raised and the can 13 of paint to be mixed is inserted on the lower shoe 12. The arm 23 is then lowered to engage the upper end of the can with the upper shoe and the arm is locked in place by threading down the set screw 26. With the paint can properly positioned, the valve lever 31 is rotated to admit air to the motor which causes the disc 7 to rotate providing an oscillating action for the can. The flexible and resilient shoes 12 and 14 along with the spring 20', which connects the upper shoe 14 to the supporting arm 23, coact with the oscillating drive in providing a rapid and effectively mixes the pigment in the paint.

The present invention is considerably cheaper than a conventional paint mixing mechanism which requires a built-in motor and drive mechanism. In the present instance, the pneumatic drive mechanism of a standard oscillating sander is incorporated to provide the driving force for the paint mixing unit of the invention. This substantially reduces the overall cost of the mixing unit, and makes the unit available to small auto body shops and other establishments which would not ordinarily purchase conventional paint mixing equipment.

The supporting shoes 12 and 14 are designed so that they will readily accommodate a pint, quart or gallon of paint without alteration. Thus, any normally used can may be mixed without having to replace the shoes.

The stud 39 which engages the trigger 35 enables the unit to be unattended during the mixing operation. If the stud did not depress the trigger, it would be necessary for the operator to hold the trigger in the depressed position during the mixing operation. However, with use of the stud which automatically depresses the trigger, the unit can be unattended so that the operator can perform other duties during the paint mixing procedure.

Various modes of carrying out the invention are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention.

I claim:

1. In an apparatus for mixing a material, a base, a mounting member connected to the base, a portable fluid drive unit removably supported in said mounting member and including a fluid-operated motor and a motor drive shaft, said drive unit also having a passage for the flow of fluid and having a trigger-actuated valve to control the flow of fluid through said passage, a first shoe disposed to support a container of the material to be mixed, means for eccentrically connecting the first shoe to the motor drive shaft, a second shoe disposed in alignment with the first shoe and disposed to engage the upper end of said container, support means connected to the base, and resilient means for resiliently connecting the support means to said second shoe.

2. The apparatus of claim 1, wherein said fluid drive unit includes a handle and said passage is located within said handle, and said apparatus includes means extending upwardly from the base and disposed to engage the trigger and open said valve when said fluid drive unit is supported in said mounting member.

3. The apparatus of claim 1 in which said resilient means is a coil spring.

4. The apparatus of claim 1, in which said first and second shoes are each provided with a series of concentric circular abutments disposed to engage the ends of containers of different standard sizes.

5. The apparatus of claim 1, in which said support means includes a column extending outwardly from the base and an arm adjustably connected to said column and secured to said resilient means.

6. The apparatus of claim 1, in which said mounting member is cup-shaped and receives the motor of said drive unit and is provided with a notch to receive said handle. 7. A mixing apparatus for mixing a material in a closed container, comprising a base, a mounting member con nected to the base, a separate pneumatic drive unit including a motor removably mounted in said mounting member and having a motor drive shaft projecting upwardly from said motor, said unit also including a handle having a passage for the flow of air to said motor and including air flow control means for controlling the flow of air through said passage, said control means including an operating member located on the exterior of the unit,

trigger actuated valve to control the flow of air in said passage, means extending upwardly from said base and disposed to engage said operating member and actuate said control means to open said passage to the flow of air when the motor is positioned in said mounting member, a lower flexible shoe disposed to engage and support the lower end of a container for the material to be mixed, means for eccentrically connecting the lower shoe to the motor drive shaft, an upper flexible shoe disposed to engage the upper end of the container, support means extending upwardly from the base, and resilient means for resiliently connecting the upper shoe to the support means. 10

6 9. The apparatus of claim 7 in which the shoes are generally disc-like in shape, and said resilient means comprises a coil spring connected between the support means and the central portion of the upper shoe.

References Cited UNITED STATES PATENTS 1,960,640 5/1934 Lajeunesse 259-75 2,797,902 8/ 1957 Beugler 25972 3,061,280 10/1962 Kraft 259-72 WALTER A. SCHEEL, Primary Examiner.

ROBERT W. JENKINS, Examiner. 

1. IN A APPARATUS FOR MIXING A MATERIAL, A BASE, A MOUNTING MEMBER CONNECTED TO THE BASE, A PORTABLE FLUID DRIVE UNIT REMOVABLY SUPPORTED IN SAID MOUNTING MEMBER AND INCLUDING A FLUID-OPERATED MOTOR AND A MOTOR DRIVE SHAFT, SAID DRIVE UNIT ALSO HAVING A PASSAGE FOR THE FLOW OF FLUID AND HAVING A TRIGGER-ACTUATED VALVE TO CONTROL THE FLOW OF FLUID THROUGH SAID PASSAGE, A FIRST SHOE DISPOSED TO SUPPORT A CONTAINER OF THE MATERIAL TO BE MIXED, MEANS FOR ECCENTRICALLY CONNECTING THE FIRST SHOE TO THE 